That includes soldiers from the Army, Marine Corps, National Guard, and their reserves who had served or were serving in Iraq by the end of 2005. When all U. S. military forces are counted--including Air Force and Navy pilots, as well as support personnelfrom all uniformed military branches--the number of Americans who have served in or around Iraq since Operation Iraqi Freedom began in March 2003 approaches one million. For comparison, a total of 2.6 million U. S. combat soldiers (not including support personnel) served in Vietnam during the fourteen years of that conflict. Just under 200,000 American soldiers served in combat during the Korean War.

FRACTION OF THE ARMY'S ACTIVE-DUTY FORCE DEPLOYED IN IRAQ AND AFGHANISTAN: 63 PERCENT

This includes all army personnel deployed since the U. S.-led operations in those nations were initiated in October 2001. Of the army personnel sent to Iraq or Afghanistan, nearly 40 percent have been redeployed--served an additional tour of duty--at least once.

NUMBER OF AMERICAN TROOPS SERIOUSLY INJURED OR WOUNDED: 16,155

Of those counted as seriously wounded since the beginning of Operation Iraqi Freedom through the end of 2005, 7,529 were listed as "WIA/not RTD"--Wounded in Action, Not Returned to Duty. Put in civilian terms, this means that nearly half of all combat-related injuries in Iraq have been so serious that they've prevented the soldier from continuing his or her military service. (Comparable figures for Vietnam and other wars are hard to calculate, since WIA/not RTD is a new statistic.) In addition, there were 2,173 deaths, of which 1,705 occurred in combat.

Of all the numbers presented here, this may be the most astonishing. No military in history has been so good at keeping its fallen soldiers alive. This number is a dramatic improvement from the first Gulf war, in 1991, and from Vietnam in the 1960s and 1970s, during which one fourth of all U. S. combat injuries proved fatal. The main reasons soldiers are surviving seem to be, first, the widespread use of body armor (which, despite ongoing criticism of its quality, offers some protection to the torso and vital organs) and also the deployment of forward surgical teams to or directly behind combat lines, which provide sophisticated trauma care and emergency surgery in the field. The most seriously injured are evacuated to permanent hospitals in Iraq within hours, to U. S. military hospitals in Europe within two days, and, in the most dire cases, to Walter Reed Army Medical Center in Washington, D. C., within four days. During the Vietnam era, that same trip took an average of six weeks. Most soldiers killed in Vietnam died without ever receiving professional medical help.

NUMBER OF AMPUTATIONS AMONG IRAQ-WAR VETERANS PERFORMED AT WALTER REED ARMY MEDICAL CENTER: 285

A disturbing corollary of the military's remarkable success in saving wounded Iraq-war soldiers is the high number of survivors who undergo single or multiple amputations (at Walter Reed and other military hospitals) and/or live with disfiguring or disabling head, face, and spinal injuries. According to a 2004 U. S. Senate report, 6 percent of injured troops in Iraq have required amputations, twice the rate of any previous war.

Of course, amputation, disfigurement, and disablement dramatically change life for those who experience them, affecting mobility, employability, and sexual activity, as well as having secondary health effects. Not surprisingly, depression, self-doubt, and self-isolation are common psychological consequences. (The recently announced closure of Walter Reed by 2011--and the integration of its services into the nearby National Naval Medical Center--has put the construction of its planned large amputee training center on hold; a less expensive, temporary center is being built instead.)

In April 2004, the Army created the Disabled Soldier Support System, essentially a clearinghouse with a dedicated phone number through which seriously injured veterans can learn about the government benefits and treatments available to them. Its name has since been changed to the Army Wounded Warrior Program.

THE APPROXIMATE SHARE OF ALL U. S. TROOPS IN IRAQ THAT COMES FROM THE NATIONAL GUARD: 40 PERCENT

This figure, including troops from the Army National Guard, Army Reserve, and Marine Reserve, is far higher than has been the case in any previous U. S. military campaign. The main reason is that the Iraq war is the first major war in U. S. history that has been waged without the draft; during Vietnam, National Guard and Reserve troops rarely served in combat zones. Often unremarked upon is the fact that National Guard soldiers are not a replacement for enlisted troops in Iraq; they are a critical supplement to them. Nearly two thirds of the Army's enlisted soldiers have been sent to Iraq or Afghanistan at least once; the rest are needed for operations elsewhere.

The readjustment of Guard and Reserve soldiers to civilian life is of great concern to both the military and veterans' advocacy groups, as well as the VA. Studies conducted by the Army in Iraq show that they are far more susceptible to post-traumatic stress disorder (PTSD) than enlisted soldiers and, perhaps relatedly, significantly more likely to describe themselves as having low morale and feeling unprepared for combat. Anticipating difficulties with readjustment, the Department of Defense has extended federal insurance and medical-treatment benefits for National Guard and Reserve troops. They are now eligible for a year of the DOD's Tricare medical coverage for every ninety consecutive days of service.

According to a 2005 Department of Veterans Affairs study of nearly 170,000 Operation Iraqi Freedom veterans, roughly 34,000 were diagnosed with psychological disorders, including 1,641 identified as suffering full-fiedged post-traumatic stress disorder. Overall, more than 9,600 Iraq veterans have been provisionally diagnosed with PTSD by the VA. More generally, about 12,500 Iraq veterans have contacted the VA seeking help for psychological difficulties in readjusting to civilian life, according to another 2005 VA study.

PTSD is of particular concern to the VA and veterans' support groups, as it is closely linked with domestic violence, depression, unemployment, and homelessness. Adding to fears is the change in the nature of war in Iraq from traditional combat to guerrilla or insurgent warfare. Because violence in the latter affects not only soldiers but medics, administrators, and other support staff, a larger number of Americans in Iraq are exposed to the conditions that frequently cause PTSD: violence, unpredictable attacks, and a constant sense of vulnerability.

NUMBER OF IRAQ AND/OR AFGHANISTAN VETERANS CONFIRMED TO BE HOMELESS: 500

That is the number reported by the National Coalition for Homeless Veterans (NCHV), which compiles records from public and private agencies and which believes that the actual number is higher and likely to grow. Nationwide, there are at least 500,000 homeless American veterans, according to the NCHV. One half of them--roughly 250,000 men--fought in Vietnam. If accurate, that would amount to about 10 percent of American soldiers who fought in Vietnam.

UNEMPLOYMENT RATE AMONG ALL VETERANS UNDER AGE TWENTY-FIVE: 15 PERCENT

That figure is more than twice the rate for the same demographic in the general population. Partly in response, in 2005 the Department of Veterans Affairs launched a program to help place veterans in jobs after they return home.

In addition, a 2004 Harvard study estimated that one in three veterans under the age of twenty-five lacks health insurance.

That was the prediction of the VA in testimony to Congress in 2003. Congress increased the VA's medical budget by about 1 percent in 2005 and by less than 3 percent for 2006. In June of last year, the VA stated that due to greatly increased costs, its 2006 medical budget fell nearly $2 billion short of its immediate needs.